Fertilization = Male gamete + Female gamete = Single Cell.

• Think of it like mixing two magical ingredients to create the starting point of life!

• This single cell (from fertilization) doesn't remain alone. It starts dividing to make an embryo with many cells.
• The method of division? Mitosis.
  • Mitosis is like a cloning machine; it ensures every new cell is an identical twin!

• Cells in an early-stage embryo are like Jack-of-all-trades: they're unspecialized.
• As they grow, they choose career paths! They specialize and get better at specific jobs. This is like picking your favorite subject in school and becoming an expert in it.
• This career choice? Called Differentiation.

• Differentiation: Process where cells develop differently to do specific tasks.
  • E.g., Some cells decide to pump blood (heart cells), while others become great at protecting our body (skin cells).
• Why specialize? Specialized cells are more efficient!
  • Imagine if a chef also had to be a firefighter and a pilot at the same time. Exhausting, right? Specialization lets the cell be the best at one job.